There exist valves which are adapted to be hydraulically operated. In examining the prior art with respect to them, one such type valve appears. In it, a pair of spaced annular pistons are connected together by a tubular sleeve, and a sealing shoulder is positioned around this tubular sleeve between the annular pistons. By this combination, two expansion-contraction chambers are formed. A valve plunger is positioned on the end of the tubular sleeve, and fluid flow, normally being through the center of the sleeve, is blocked or unblocked by the valve action of the plunger. Since the pistons are at opposite ends of the assembly and the chambers intermediate them, inherently, the whole structure is lengthy and not adaptable to construction for employment in confined spaces.
It is an object of this invention to provide an improved hydraulically operated valve which is extremely compact and thus positionable in restricted spaces, and at the same time is of simpler construction than valves of the type described and less costly to manufacture and supply to users.